title: Small human sperm vacuoles observed under high magnification are pocket-like nuclear concavities linked to chromatin condensation failure.
abstract: Since an embryo's ability to grow to the blastocyst stage and implant can be improved by selection of a normal spermatozoon with a vacuole-free head, this study set out to determine the nature of small sperm vacuoles observed under high magnification (>×6300). For 15 infertile men with various sperm profiles, high-magnification microscopy was used to select motile, morphometrically normal spermatozoa with no vacuoles (n=450) or more than two small vacuoles (each of which occupied less than 4% of the head's area; n=450). Spermatozoa acrosome reaction status and degree of chromatin condensation were analysed. Three-dimensional deconvolution microscopy was used to accurately image the nucleus and acrosome at all depths in all spermatozoa. In all 450 spermatozoa with small vacuoles, the latter were seen to be abnormal, DNA-free nuclear concavities. Spermatozoa with small vacuoles were significantly more likely than vacuole-free spermatozoa to have noncondensed chromatin (39.8% versus 9.3%, respectively; P<0.0001). There was no significant difference between the two groups of spermatozoa in terms of acrosome reaction status. No association between chromatin condensation and acrosome reaction status was observed. Small human sperm vacuoles observed under high magnification are pocket-like nuclear concavities related to failure of chromatin condensation.
authors.affiliation: Department of Reproductive Biology, Cytogenetics and Gynaecology, Poissy General Hospital, F-78303 Poissy, France. florenceboitrelle@yahoo.fr
authors.forename: F
authors.initials: F
authors.lastname: Boitrelle
authors.forename: M
authors.initials: M
authors.lastname: Albert
authors.forename: J-M
authors.initials: JM
authors.lastname: Petit
authors.forename: F
authors.initials: F
authors.lastname: Ferfouri
authors.forename: R
authors.initials: R
authors.lastname: Wainer
authors.forename: M
authors.initials: M
authors.lastname: Bergere
authors.forename: M
authors.initials: M
authors.lastname: Bailly
authors.forename: F
authors.initials: F
authors.lastname: Vialard
authors.forename: J
authors.initials: J
authors.lastname: Selva
mesh_terms: D000177:Acrosome / Q000378:metabolism / Q000473:pathology; D020101:Acrosome Reaction; D000328:Adult; D053627:Asthenozoospermia / Q000473:pathology / Q000503:physiopathology; D002467:Cell Nucleus / Q000378:metabolism / Q000473:pathology*; D053144:Cell Nucleus Shape; D002843:Chromatin / Q000378:metabolism / Q000473:pathology*; D042002:Chromatin Assembly and Disassembly; D004247:DNA / Q000378:metabolism; D006801:Humans; D021621:Imaging, Three-Dimensional; D007248:Infertility, Male / Q000473:pathology* / Q000503:physiopathology; D008297:Male; D008857:Microscopy, Interference; D012720:Severity of Illness Index; D059010:Single-Cell Analysis; D013077:Sperm Head / Q000378:metabolism / Q000473:pathology; D013081:Sperm Motility; D013094:Spermatozoa / Q000378:metabolism / Q000473:pathology*; D014617:Vacuoles / Q000378:metabolism / Q000473:pathology*
chemical_list: D002843:Chromatin; D004247:DNA
keywords: IMSI; MSOME; acrosome; aniline blue; nuclear concavity; sperm vacuole